US food giant Kraft has said it hopes to invest in Cadbury's factory near Birmingham, saying it will remain "financially disciplined" in its £10.2bn pursuit of the chocolate maker.

The firm was attempting to dampen down hopes for a bidding war for the firm after Cadbury snubbed its surprise approach.

Kraft hopes to keep open Cadbury's Somerdale facility near Bristol, which is due to close in early 2010, while investing in the firm's Bournville factory near Birmingham.

Kraft has offered 745p in cash and shares for the confectioner, but Cadbury shares surged more than 5% above this level amid speculation about a higher bid and interest from rivals such as Hershey or Nestle.

Kraft's executive vice president, Michael Osanloo, said: "The simple fact is that Cadbury is worth what someone is willing to pay for it - nothing more. We are the most logical buyer but we will remain financially disciplined."

Analysts have suggested that Kraft's bid undervalued the firm in comparison with Mars' takeover of gum giant Wrigley last year, although Mr Osanloo said "the world has changed dramatically since then".

But Numis analyst Nicholas Ceron set a target price of 880p for Cadbury which would value the firm at £12bn.

Cadbury has said Kraft's proposal "fundamentally undervalues the group and its prospects". A takeover would mark the biggest in the UK sweets sector since Nestle bought Rowntree in 1988.

A deal between Kraft and Cadbury, which is the world's second biggest confectionery firm behind Mars, would create a "global powerhouse" with annual sales of around 50bn (£30.5bn), according to Kraft.

The would-be buyer has also sought to give assurance that a deal between the two would see jobs protected and possibly even created.